The present invention relates to a tubular extension particularly but not exclusively useful for electric household appliances and for cleaning machines in general.
It is known that electric household appliances for aspirating dust and liquids are currently particularly used and appreciated.
In particular, these electric household appliances, in order to be used advantageously and effectively, must allow a good working range without forcing the operator to change the power source, which is usually a mains outlet.
These electric household appliances must also have a structure which allows easy and ergonomic positions for the operator even in situations in which it is necessary to clean surfaces which are particularly difficult because of their location (consider for example the cleaning of a ceiling or of particularly hard to access corners, or floors whereon pieces of furniture are provided which have a fixed base or are in any case difficult to move).
In order to extend the working range of these electric household appliances, extensions are currently used which have substantially similar structures despite their differences in embodiment.
In particular, the solution which provides for the mutual insertion coupling of tubular segments which are interconnected by simple interlocking or by means of couplings, for example bayonet couplings, is particularly used in commercially available electric household appliances.
This solution with mutually insertion-coupled segments, though performing its function, is not free from drawbacks, the main one being the fact that the ducts are extended by preset segments the length whereof cannot be very limited since the operator might then be forced to assemble an excessively large number of segments, wasting time and producing structures which are not perfectly stable.
Telescopic extensions, in which the associated tubular elements are kept locked by pressing the free ends of threaded elements whose screwing and unscrewing movement produces length adjustment and allows actual use of the extension, are more rarely commercially available.
However, even this last solution entails drawbacks, one of which is a certain constructive complexity and a sometimes ineffective positional stability during use.